import java.util.Scanner;

public class Test4 {
    public static boolean isHuiWen(String str){
        int left=0;
        int right=str.length()-1;
        while(left<right){
            if(str.charAt(left)!=str.charAt(right)){
                return false;
            }
            left++;
            right--;
        }
        return true;
    }
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        String str=sc.nextLine();
        boolean flag=isHuiWen(str);
        if(flag==false){
            System.out.print("no");
        }
        else{
            System.out.print("yes");
        }

    }
}
